This invention concerns impact protecting guard beams for doors of motor vehicles, which have come into widespread application. Such beams are positioned horizontally within the door at approximately the mid-level of the door and are intended to protect the passenger compartment from penetration in the event of a side impact collision.
These beams are thus of sturdy construction to resist bending. These beams are securely attached at either end to the hinge and lock hem flanges of the door, as by welding of tabs formed on the beam ends to the door hem flanges.
While guard beams have been quite successful in improving vehicle safety, the deformation of the beam during a collision has been found to have a tendency to twist the lock mounting door edge to such an extent that the door lock mating components become disengaged, allowing the doors to immediately pop open in a collision. This tendency itself creates a safety hazard and must be avoided by a lengthy process of experimentally determining the configuring of the beam and door details which will avoid this tendency. This need for a substantial design effort to avoid this problem adds a great burden to the development of each new vehicle design.
The object of the present invention is to provide a protective beam for motor vehicle side doors which minimizes the tendency for twisting of the door lock mounting edge structure particularly in the early stages of a collision.